Abstract:
In order to study the reasons and influence factors of subsequent cracking in punch-out areas, cement concrete which is constituted by cementing materials, aggregates and their interfaces were taken into consideration. Firstly, compressive strength test and flexural tensile strength test in meso-scale were simulated by using PFC2D software, and elastic modulus and flexural tensile strength were obtained. Secondly, considering the characteristics of continuously reinforced concrete pavement (CRCP) punch-out area and combining the elastic modulus and flexural tensile strength which were obtained from compressive strength test and flexural tensile strength test, the mechanics model of CRCP in macro-scale was established by the finite element method software and the subsequent cracking of CRCP punch-out area under vehicle load, temperature and moisture gradient was analyzed. Lastly, influence factors of the constitution factors of concrete in meso-scale and pavement factors in macro-scale on subsequent cracking of CRCP punch-out area were analyzed.The results based on the study of two scale model for macro-scale and meso-scale indicate that cement content, cement strength and interface stiffness of aggregate and cementing materials have large influence on subsequent cracking of CRCP punch-out area, vehicle overload and void at the bottom of pavement are the main reasons for subsequent cracking of CRCP punch-out area.